This application claims priority from Korean Patent Application No. 2002-9088, filed on Feb. 20, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to an electron amplifier and a method of manufacturing the same, and more particularly, to an electron amplifier utilizing carbon nanotubes and a method of manufacturing the electron amplifier.
2. Description of the Related Art
Electron amplifiers include a secondary electron emission layer in order to induce emission of secondary electrons. Electron amplifiers are based on the principle that if primary electrons are accelerated to collide with the secondary electron emission layer, bound electrons on the surface of the secondary electron emission layer absorb the kinetic energy of the primary electrons, and are then emitted as secondary electrons.
Electron amplifiers are generally used in measuring equipment, such as, mass analyzers, surface analyzers, energy analyzers, and the like, and are also used in night goggles, display devices, and the like.
FIG. 1A is a cross-section of a conventional electron amplifier 10. Referring to FIG. 1A, the conventional electron amplifier 10 includes a substrate 13, electrode layers 14 and 15 formed on the upper and lower surfaces of the substrate 13, respectively, a through hole 11 formed perpendicular to the electron layers 14 and 15, a resistive layer 16 formed along the inner wall of the through hole 11, and an electron emission layer 17 formed covering the resistive layer 16.
FIG. 1B illustrates a method of manufacturing a conventional electron amplifier. As shown in step (a), a core glass 22 which melts in a chemical etching solution and a lead glass 21 which does not melt in the chemical etching solution are prepared. As shown in step (b), the core glass 22 fits into the lead glass 21 to obtain a single glass pipe 23. Thereafter, the single glass pipe 23 is stretched to obtain a thin glass fiber 23′ as shown in step (c). Then, glass fibers 23′ are tied into a hexagonal bundle 24 as shown in step (d). Next, the hexagonal bundle is stretched out to obtain a thin hexagonal multiple fiber 25 as shown in step (e). Next, hexagonal multiple fibers 25 are tied into a bundle 26, and the bundle 26 is then attached to a glass skin to be shaped as shown in step (f). The bundle 26 is then thinly cut to obtain a wafer 27 as shown in step (g).
Next, the surface of the wafer 27 is polished, and the core glass 22 of the glass fiber 23′ is etched using an appropriate etching solution. Then, the resultant wafer 27 undergoes a chemical process for increasing the secondary electron emission property of the wall of the glass fiber 23′ and is then reduced in a hydrogen-ambient baking furnace. During this reduction, lead oxide on the glass surface turns into conductive lead and water, and lead particles form lumps. If the temperature is high, lead particle lumping prevails over new lead particle formation. Thus, the resistance between two electrodes is not determined by lead particles but by the temperature in the baking furnace.
Finally, an electrode is formed of Inconel or Nichrome on the baked wafer 27, thereby completing a microchannel plate.
The electrical operation characteristics of electron amplifiers are usually determined by their resistance, which in turn is determined by the ratio of the length of a through hole to the diameter thereof. Accordingly, it is difficult for conventional electron amplifiers to obtain a desired electron emission efficiency, for example, an electron emission efficiency of 103 through 105 times as much as a primary electron emission efficiency.